1. Field of the Invention
The present invention relates to a locking structure for an armrest installed at a rear seat in a passenger vehicle. More particularly, the present invention relates to a locking structure for a center armrest installed at a center of a rear seat, which prevents an operation defect caused by friction between internal components while performing a locking operation or a releasing operation, and which maintains a locked state more securely even in the event of a rear-end collision of a vehicle.
2. Description of the Related Art
Typically, in the case of a passenger vehicle, unlike a front seat structure in which a driver seat and a front passenger seat are mounted separately, a rear seat has a structure disposed to be elongated within a vehicle width direction to allow at least three persons to be seated in the rear seat. Further, in accordance with the specifications of the vehicle, a (center) armrest may be selectively installed at a center of the rear seat. As illustrated in FIG. 1A of the related art, the armrest may be folded up to ensure a space for seating multiple persons and may be pulled down when one or two persons are seated.
The armrest has a structure in which an armrest housing 1a is pivotably coupled to an armrest bracket 1b fixedly embedded in a backrest 2b of the rear seat so that the armrest housing 1a is placed on a seat 2a, a plurality of buttons for adjusting an interior lamp, an audio system, an air conditioner and the like when the armrest housing 1a is pulled down may be additionally mounted on the armrest, and a ski through structure, which may be partially opened, may be adopted to the armrest bracket 1b to allow for loading of skis or a board (through a trunk room). Meanwhile, to prevent a passenger from being pushed forward due to a rear-end collision when the armrest housing 1a is in a folded up position and the passenger is seated in front of the armrest housing 1a, rotation of the armrest is locked when the armrest is in the folded up position.
Referring to FIG. 1B of the related art, when describing a locking structure for an armrest, fixing plates 9 having apertures are disposed at both sides of the armrest bracket 1b, a knob 3, which is operable from the exterior, is connected with hinge links 6 through a cable 4 inside the armrest housing 1a, and the hinge links 6 are pivotably mounted on the bracket 5 by pulling the cable 4. Further, ends of the hinge links 6 are connected with ends of locking pins 8 coupled to springs, and thus, when the occupant operates the knob 3, the locking pins 8 slide in a longitudinal direction.
Therefore, when the armrest housing 1a is in the folded up position in a state in which the fixing plates 9 mounted to the armrest bracket 1b are fixed, the ends of the locking pins 8 are aligned at positions where the ends of the locking pins 8 may be inserted into the apertures in the fixing plates 9, and when the locking pins 8 are inserted into the apertures, rotation of the armrest housing 1a is locked, and when the locking pins 8 are withdrawn from the apertures by operating the knob 3 in the locked state, the armrest housing 1a is unlocked allowing rotation thereof to a pulled down position.
However, for the structure in the related art, there is a likelihood that the locking pins cannot properly be inserted into the apertures due to a gap formed between the locking pins and the aperture, or alignment is not properly performed. Therefore, the armrest housing may be inadvertently pulled down in the event of a rear-end collision in a case in which a locking operation is not normally performed. Furthermore, friction may occur when the locking pins are inserted into the apertures, and force required to operate the knob may be excessively increased.